Get rid of extern "C" in module boot()/init()

We will have a separate (extern "C") register() function that will return
the pointers to these two. This way we can still throw exceptions from
boot() and init().

16 files changed, 153 insertions, 149 deletions

diff --git a/build2/b.cxx b/build2/b.cxx
index 633d583..e7c8721 100644
--- a/build2/b.cxx
+++ b/build2/b.cxx
@@ -185,18 +185,16 @@ main (int argc, char* argv[])
 
     // Register builtin modules.
     //
-    builtin_modules["config"]  = module_functions {&config::config_boot,
-                                                   &config::config_init};
-    builtin_modules["dist"]    = module_functions {&dist::dist_boot,
-                                                   &dist::dist_init};
-    builtin_modules["test"]    = module_functions {&test::test_boot,
-                                                   &test::test_init};
-    builtin_modules["install"] = module_functions {&install::install_boot,
-                                                   &install::install_init};
-
-    builtin_modules["bin"] = module_functions {nullptr, &bin::bin_init};
-    builtin_modules["cxx"] = module_functions {nullptr, &cxx::cxx_init};
-    builtin_modules["cli"] = module_functions {nullptr, &cli::cli_init};
+    builtin_modules["config"]  = module_functions {&config::boot,
+                                                   &config::init};
+    builtin_modules["dist"]    = module_functions {&dist::boot, &dist::init};
+    builtin_modules["test"]    = module_functions {&test::boot, &test::init};
+    builtin_modules["install"] = module_functions {&install::boot,
+                                                   &install::init};
+
+    builtin_modules["bin"] = module_functions {nullptr, &bin::init};
+    builtin_modules["cxx"] = module_functions {nullptr, &cxx::init};
+    builtin_modules["cli"] = module_functions {nullptr, &cli::init};
 
     // Figure out work and home directories.
     //
diff --git a/build2/bin/module b/build2/bin/module
index 0b9d44e..e74cbe2 100644
--- a/build2/bin/module
+++ b/build2/bin/module
@@ -14,14 +14,14 @@ namespace build2
 {
   namespace bin
   {
-    extern "C" bool
-    bin_init (scope&,
-              scope&,
-              const location&,
-              unique_ptr<module_base>&,
-              bool,
-              bool,
-              const variable_map&);
+    bool
+    init (scope&,
+          scope&,
+          const location&,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&);
   }
 }
 
diff --git a/build2/bin/module.cxx b/build2/bin/module.cxx
index d5df054..70a2b98 100644
--- a/build2/bin/module.cxx
+++ b/build2/bin/module.cxx
@@ -30,14 +30,14 @@ namespace build2
     static const strings liba_lib {"static"};
     static const strings libso_lib {"shared"};
 
-    extern "C" bool
-    bin_init (scope& r,
-              scope& b,
-              const location&,
-              unique_ptr<module_base>&,
-              bool first,
-              bool,
-              const variable_map& config_hints)
+    bool
+    init (scope& r,
+          scope& b,
+          const location&,
+          unique_ptr<module_base>&,
+          bool first,
+          bool,
+          const variable_map& config_hints)
     {
       tracer trace ("bin::init");
       l5 ([&]{trace << "for " << b.out_path ();});
diff --git a/build2/cli/module b/build2/cli/module
index f55e03c..50d07ef 100644
--- a/build2/cli/module
+++ b/build2/cli/module
@@ -14,14 +14,14 @@ namespace build2
 {
   namespace cli
   {
-    extern "C" bool
-    cli_init (scope&,
-              scope&,
-              const location&,
-              unique_ptr<module_base>&,
-              bool,
-              bool,
-              const variable_map&);
+    bool
+    init (scope&,
+          scope&,
+          const location&,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&);
   }
 }
 
diff --git a/build2/cli/module.cxx b/build2/cli/module.cxx
index 13325d9..01d606f 100644
--- a/build2/cli/module.cxx
+++ b/build2/cli/module.cxx
@@ -25,14 +25,14 @@ namespace build2
   {
     static compile compile_;
 
-    extern "C" bool
-    cli_init (scope& root,
-              scope& base,
-              const location& loc,
-              unique_ptr<module_base>&,
-              bool first,
-              bool optional,
-              const variable_map& config_hints)
+    bool
+    init (scope& root,
+          scope& base,
+          const location& loc,
+          unique_ptr<module_base>&,
+          bool first,
+          bool optional,
+          const variable_map& config_hints)
     {
       tracer trace ("cli::init");
       l5 ([&]{trace << "for " << base.out_path ();});
diff --git a/build2/config/module b/build2/config/module
index 912ab57..adc9b05 100644
--- a/build2/config/module
+++ b/build2/config/module
@@ -28,17 +28,17 @@ namespace build2
       static const string name;
     };
 
-    extern "C" void
-    config_boot (scope&, const location&, unique_ptr<module_base>&);
-
-    extern "C" bool
-    config_init (scope&,
-                 scope&,
-                 const location&,
-                 unique_ptr<module_base>&,
-                 bool,
-                 bool,
-                 const variable_map&);
+    void
+    boot (scope&, const location&, unique_ptr<module_base>&);
+
+    bool
+    init (scope&,
+          scope&,
+          const location&,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&);
   }
 }
 
diff --git a/build2/config/module.cxx b/build2/config/module.cxx
index 70301c5..4f4064f 100644
--- a/build2/config/module.cxx
+++ b/build2/config/module.cxx
@@ -27,8 +27,8 @@ namespace build2
     //
     static const path config_file ("build/config.build");
 
-    extern "C" void
-    config_boot (scope& root, const location&, unique_ptr<module_base>&)
+    void
+    boot (scope& root, const location&, unique_ptr<module_base>&)
     {
       tracer trace ("config::boot");
 
@@ -53,14 +53,14 @@ namespace build2
         source (f, root, root);
     }
 
-    extern "C" bool
-    config_init (scope& root,
-                 scope&,
-                 const location& l,
-                 unique_ptr<module_base>& mod,
-                 bool first,
-                 bool,
-                 const variable_map& config_hints)
+    bool
+    init (scope& root,
+          scope&,
+          const location& l,
+          unique_ptr<module_base>& mod,
+          bool first,
+          bool,
+          const variable_map& config_hints)
     {
       tracer trace ("config::init");
 
diff --git a/build2/cxx/module b/build2/cxx/module
index 254eb44..37466ef 100644
--- a/build2/cxx/module
+++ b/build2/cxx/module
@@ -14,14 +14,14 @@ namespace build2
 {
   namespace cxx
   {
-    extern "C" bool
-    cxx_init (scope&,
-              scope&,
-              const location&,
-              unique_ptr<module_base>&,
-              bool,
-              bool,
-              const variable_map&);
+    bool
+    init (scope&,
+          scope&,
+          const location&,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&);
   }
 }
 
diff --git a/build2/cxx/module.cxx b/build2/cxx/module.cxx
index 7e9b5e2..71304c8 100644
--- a/build2/cxx/module.cxx
+++ b/build2/cxx/module.cxx
@@ -29,14 +29,14 @@ namespace build2
 {
   namespace cxx
   {
-    extern "C" bool
-    cxx_init (scope& r,
-              scope& b,
-              const location& loc,
-              unique_ptr<module_base>&,
-              bool first,
-              bool,
-              const variable_map& config_hints)
+    bool
+    init (scope& r,
+          scope& b,
+          const location& loc,
+          unique_ptr<module_base>&,
+          bool first,
+          bool,
+          const variable_map& config_hints)
     {
       tracer trace ("cxx::init");
       l5 ([&]{trace << "for " << b.out_path ();});
diff --git a/build2/dist/module b/build2/dist/module
index 984a969..3c43c1f 100644
--- a/build2/dist/module
+++ b/build2/dist/module
@@ -14,17 +14,17 @@ namespace build2
 {
   namespace dist
   {
-    extern "C" void
-    dist_boot (scope&, const location&, unique_ptr<module_base>&);
+    void
+    boot (scope&, const location&, unique_ptr<module_base>&);
 
-    extern "C" bool
-    dist_init (scope&,
-               scope&,
-               const location&,
-               unique_ptr<module_base>&,
-               bool,
-               bool,
-               const variable_map&);
+    bool
+    init (scope&,
+          scope&,
+          const location&,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&);
   }
 }
 
diff --git a/build2/dist/module.cxx b/build2/dist/module.cxx
index 58bfc6f..eed9562 100644
--- a/build2/dist/module.cxx
+++ b/build2/dist/module.cxx
@@ -22,8 +22,8 @@ namespace build2
   {
     static rule rule_;
 
-    extern "C" void
-    dist_boot (scope& r, const location&, unique_ptr<module_base>&)
+    void
+    boot (scope& r, const location&, unique_ptr<module_base>&)
     {
       tracer trace ("dist::boot");
 
@@ -54,14 +54,14 @@ namespace build2
       }
     }
 
-    extern "C" bool
-    dist_init (scope& r,
-               scope&,
-               const location& l,
-               unique_ptr<module_base>&,
-               bool first,
-               bool,
-               const variable_map& config_hints)
+    bool
+    init (scope& r,
+          scope&,
+          const location& l,
+          unique_ptr<module_base>&,
+          bool first,
+          bool,
+          const variable_map& config_hints)
     {
       tracer trace ("dist::init");
 
diff --git a/build2/install/module b/build2/install/module
index b2a3301..3f59fee 100644
--- a/build2/install/module
+++ b/build2/install/module
@@ -14,17 +14,17 @@ namespace build2
 {
   namespace install
   {
-    extern "C" void
-    install_boot (scope&, const location&, unique_ptr<module_base>&);
+    void
+    boot (scope&, const location&, unique_ptr<module_base>&);
 
-    extern "C" bool
-    install_init (scope&,
-                  scope&,
-                  const location&,
-                  unique_ptr<module_base>&,
-                  bool,
-                  bool,
-                  const variable_map&);
+    bool
+    init (scope&,
+          scope&,
+          const location&,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&);
   }
 }
 
diff --git a/build2/install/module.cxx b/build2/install/module.cxx
index 6a7e500..5a18899 100644
--- a/build2/install/module.cxx
+++ b/build2/install/module.cxx
@@ -100,8 +100,8 @@ namespace build2
     static alias_rule alias_;
     static file_rule file_;
 
-    extern "C" void
-    install_boot (scope& r, const location&, unique_ptr<module_base>&)
+    void
+    boot (scope& r, const location&, unique_ptr<module_base>&)
     {
       tracer trace ("install::boot");
 
@@ -112,14 +112,14 @@ namespace build2
       r.operations.insert (install_id, install);
     }
 
-    extern "C" bool
-    install_init (scope& r,
-                  scope& b,
-                  const location& l,
-                  unique_ptr<module_base>&,
-                  bool first,
-                  bool,
-                  const variable_map& config_hints)
+    bool
+    init (scope& r,
+          scope& b,
+          const location& l,
+          unique_ptr<module_base>&,
+          bool first,
+          bool,
+          const variable_map& config_hints)
     {
       tracer trace ("install::init");
 
diff --git a/build2/module b/build2/module
index 314f5a6..c19f31d 100644
--- a/build2/module
+++ b/build2/module
@@ -25,7 +25,6 @@ namespace build2
     ~module_base () = default;
   };
 
-  extern "C"
   using module_boot_function =
     void (scope& root, const location&, unique_ptr<module_base>&);
 
@@ -35,7 +34,6 @@ namespace build2
   // unconfigured for as long as it is actually not used (e.g., install,
   // dist). The return value is used to set the <module>.configured variable.
   //
-  extern "C"
   using module_init_function =
     bool (scope& root,
           scope& base,
@@ -45,7 +43,21 @@ namespace build2
           bool optional,              // Loaded with using? (optional module).
           const variable_map& hints); // Configuration hints (see below).
 
+  struct module_functions
+  {
+    module_boot_function* boot;
+    module_init_function* init;
+  };
 
+  // The register() function will be written in C++ and will be called from
+  // C++ but we need to suppress name mangling to be able to use dlsym() and
+  // equivalent.
+  //
+  extern "C"
+  using module_register_function = module_functions ();
+
+  // Loaded modules state.
+  //
   struct module_state
   {
     bool boot; // True if the module boot'ed but not yet init'ed.
@@ -93,12 +105,6 @@ namespace build2
 
   // Builtin modules.
   //
-  struct module_functions
-  {
-    module_boot_function* boot;
-    module_init_function* init;
-  };
-
   using available_module_map = std::map<string, module_functions>;
   extern available_module_map builtin_modules;
 }
diff --git a/build2/test/module b/build2/test/module
index b9c3ea5..dacb364 100644
--- a/build2/test/module
+++ b/build2/test/module
@@ -14,17 +14,17 @@ namespace build2
 {
   namespace test
   {
-    extern "C" void
-    test_boot (scope&, const location&, unique_ptr<module_base>&);
+    void
+    boot (scope&, const location&, unique_ptr<module_base>&);
 
-    extern "C" bool
-    test_init (scope&,
-               scope&,
-               const location&,
-               unique_ptr<module_base>&,
-               bool,
-               bool,
-               const variable_map&);
+    bool
+    init (scope&,
+          scope&,
+          const location&,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&);
   }
 }
 
diff --git a/build2/test/module.cxx b/build2/test/module.cxx
index c20e274..3b5cf7b 100644
--- a/build2/test/module.cxx
+++ b/build2/test/module.cxx
@@ -21,8 +21,8 @@ namespace build2
   {
     static rule rule_;
 
-    extern "C" void
-    test_boot (scope& root, const location&, unique_ptr<module_base>&)
+    void
+    boot (scope& root, const location&, unique_ptr<module_base>&)
     {
       tracer trace ("test::boot");
 
@@ -49,14 +49,14 @@ namespace build2
       }
     }
 
-    extern "C" bool
-    test_init (scope& root,
-               scope&,
-               const location& l,
-               unique_ptr<module_base>&,
-               bool first,
-               bool,
-               const variable_map& config_hints)
+    bool
+    init (scope& root,
+          scope&,
+          const location& l,
+          unique_ptr<module_base>&,
+          bool first,
+          bool,
+          const variable_map& config_hints)
     {
       tracer trace ("test::init");